Camera with power zoom function and interchangeable lens with power zoom function

ABSTRACT

The present invention provides a camera system comprising: a zoom driving means driven by a battery as a power source, for varying a focal length of a taking lens; other driving means driven from the battery as a power source; a detecting means for detecting whether the other driving means are being executed or the other driving means are to be executed; and a control means for prohibiting the execution of the zoom driving means when the detecting means detects the fact that the other driving means are being executed or that the other driving means are to be executed.

This application is a continuation of application Ser. No. 07/521,664filed May 10, 1990, abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a camera with a power zoom function, aninterchangeable lens with a power zoom function, and a camera body.

2. Related Background Art

Recently, the electrification of a camera system (the combination of aninterchangeable lens having a power zoom function and a camera on whichthe interchangeable lens can be mounted) has been progressed, wherevarious controls such as automatic exposure, winding and unwinding of afilm, AF driving, stop or aperture driving, power zoom driving, andmirror-up and/or shutter charging (in case of the single lens reflexcamera system) were automatically performed by using a number of motors.Accordingly, in the conventional camera systems, a large-sized batterieswere used as power sources for performing such controls, with the resultthat the whole camera systems themselves were large-sized and weighted,thus making the transportation of the camera system difficult. Further,if a small-sized battery is utilized to make the camera systemsmall-sized, there will arise a problem that a normal or correctphoto-taking cannot be effected.

SUMMARY OF THE INVENTION

According to one aspect of this invention, the use of a small-sizedbattery is permitted and the compactness and/or light-weighting of acamera system can be attained, by prohibiting the power zoom drivingwhile other driving with other function which wastes the greater currentis being carried out.

According to another aspect of this invention, the use of a small-sizedbattery is permitted and the compactness and/or light-weighting of acamera system can be attained, by providing means for carrying out bothof driving operations with the consumption current smaller than thoseconsumed by the execution of the respective driving operations, when thepower zoom driving and the AF driving are simultaneously performed.

Other objects of this invention will be apparent from the followingdetailed description of the invention stated hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows FIGS. 1A and 1B together which is a block diagram showing amain construction of a camera system according to a preferred embodimentof the present invention;

FIGS. 2A to 2G are timing chart for driving the camera system of FIG. 1;

FIGS. 3 to 6 are flow charts showing the operation of the camera systemof FIG. 1 at an interchangeable lens side;

FIG. 7 shows FIGS. 7A and 7B together which is a block diagram showing amain construction of a camera system according to a second embodiment ofthe present invention;

FIG. 8 to 11 are flow charts showing the operation of the camera systemof FIG. 7 at an interchangeable lens side;

FIG. 12 shows FIGS. 12A and 12B together which is a block diagramshowing a main construction of a camera system according to a thirdembodiment of the present invention;

FIG. 13 shows FIGS. 13A and 13B together which is a block diagramshowing a main construction of a camera system according to a fourthembodiment of the present invention;

FIGS. 14 and 15 are flow charts showing the operation of the camerasystem of FIG. 13 at an interchangeable lens side;

FIG. 16 is a flow chart showing the operation of a camera systemaccording to a fifth embodiment of the present invention; and

FIG. 17 is a flow chart showing the operation of a camera systemaccording to a sixth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a schematic block diagram showing a main construction of acamera system according to a preferred embodiment of the presentinvention. In FIG. 1, the reference numeral 1 denotes a camera body; and50 denotes an interchangeable lens detachably mounted on the camerabody. These elements 1, 50 are connected to each other by a camera mountla and a lens mount 51a.

Within the camera body 1, there are arranged a mirror 3, a pentagonalprism 4, an eye piece 5, a photometry light receiving element 6 and aphotometry calculating circuit 7 which is connected to a film sensitiveinformation input circuit 8, a shutter control circuit 9 and amicrocomputer 10. The microcomputer 10 includes a large currentconsumption detecting section 10a for detecting whether a large currentis consumed at the camera side, and a lens movement control section 10bfor permitting and prohibiting the power zoom driving in accordance withthe information from the section 10a. The reference numeral 34 denotes afocal plane shutter; 3a denotes a mirror pivot shaft; and 3b denotes amirror actuating pin engaged by a mirror driving cam 11. The referencenumeral 12 denotes a mirror driving motor connected to a motor drivecircuit 13; and 14 denotes a film winding and unwinding motor connectedto a motor drive circuit 15. The reference numeral 16 denotes a distancesensor connected to a distance calculating circuit 17. The referencenumeral 18 denotes a battery for activating the whole camera system; 19denotes a main power source switch; and 20 denotes a DC/DC converterconnected between the battery 18 and the microcomputer 10. The referencenumeral 21 denotes a photometry/distance switch; and 22 denotes arelease switch. Incidentally, in general, the switches 21, 22 comprise atwo-stroke switch wherein upon the first stroke of a release button theswitch 21 is turned ON and upon the second stroke of the release buttonthe switch 22 is turned ON.

The reference numerals 23a-23e denote a group of contact pins arrangedat a side of the camera body 1 near the camera mount la; and 52a-52edenote a group of contact pins arranged at a side of the interchangeablelens 50 and corresponding to the contact pins 23a-23e at the camera bodyside, respectively.

At the side of the interchangeable lens 50, the reference numerals G1,G2 and G3 denote optical taking lenses; and 53 denotes a lens drivingmotor used for adjusting the focus of the lens, which motor is connectedto a lens driving circuit 54. By rotating the lens driving motor 53, anumber of pulses are inputted to a counter 62 through a ratchet 60. Thereference numeral 61 denotes a stop driving circuit connected to amicrocomputer 55 and to a conventional pulse motor 56 by which the stopor aperture is driven. The reference numeral 57 denotes a zoom drivingmotor used during the zooming operation, which motor is connected to azoom driving circuit 58. The reference numerals 59a-59e denote anencoder for transmitting the focal length of the lens to themicrocomputer 55; 63 denotes a power zoom switch; and 64 denotes achange-over switch for changing modes between the AF priority mode andthe power zoom priority mode.

Next, the operation of the camera system as constructed above will beexplained.

First of all, the main power source switch 19 of the camera body 1 isturned ON to energize the DC/DC converter 20. As a result, the converter20 supplies a constant operable voltage to the microcomputer 10. Then,when the photometry/distance switch 21 is depressed, the light amountdetected by the photometry light receiving element 6 is transmitted tothe photometry calculating circuit 7, thereby storing the exposureamount in a known manner. Further, since the photometry/distance switch21 serves also as a trigger switch for the auto-distance, when thephotometry/distance switch 21 is depressed, the distance sensor 16 isactivated in response to the command from the microcomputer 10, therebyperforming the distance calculation by means of the distance calculatingcircuit 17, determining the feeding amount of the lens, performing theconventional serial communication with the microcomputer 55 at theinterchangeable lens side, and transmitting the rotational direction ofthe lens driving motor 53 to the lens driving circuit 54 to shift theoptical taking lens G1 in a known manner. At the same time, the contentsof the counter 62 is varied through the ratchet 60 in response to themovement of the optical taking lens G1. However, since the microcomputer55 can detect the shifting amount of the lens by reading the number ofpulses counted by the counter, the optical taking lens G1 can be shiftedin accordance with the shifting amount of the lens commanded from thecamera body side as mentioned above, and can be stopped at a focusedposition. Generally, the distance determining operation is performedonce more, and, when the focused condition is ascertained, the focusindication such as visual indication or audible indication is given atthe camera body side 1.

Next, a further operation will be explained with reference to a timingchart shown in FIG. 2. Incidentally, it should be noted that theprevious operation as mentioned above was performed prior to the "0"point shown in FIG. 2. In FIG. 2, the abscissa indicates "time" and theordinate indicates "items".

At the 0 point in FIG. 2, when the release switch 22 is depressed, themicrocomputer energizes the motor drive circuit 13 to rotate the mirrordriving motor 12, thereby rotating the mirror actuating cam 11 to liftthe actuating pin 3b (a point "a" in FIG. 2), whereby the mirror islifted and hold at that position (a point "d" in FIG. 2). At a point "b"having a given time delay from the point "a", the conventional serialcommunication is performed between the microcomputer 10 at the camerabody side and the microcomputer 55 at the lens side through the groupsof contact pins 23a, 23b, 52a, 52b thereby demanding the stop (aperture)setting value according to the photometry amount to the lens side. Thestop setting value demanded by the camera body 1 is used in the stopdriving circuit 61 as a signal for controlling the pulse motor 56. Inthis case, the reason why where is a given time delay between the pointat which the lifting movement of the mirror is started (the point "a" inFIG. 2) and the point at which the stop is started to be driven (thepoint "b" in FIG. 2) is that, since the large current flows through themirror driving motor 12 immediately after the power source switch hasbeen turned ON, the stop driving operation should be inhibited duringthat period, thereby utilizing the limited power source moreeffectively.

Incidentally, the duration between the points "b" and "c" indicates thetime when the stop-down of the stop is being effected; the point "c"indicates the time point when the stop-down has just been finished; andthe duration between points "e" and "f" indicates the shutter time(seconds) controlled by the calculated result by means of the photometrycalculating circuit 7 upon opening of the shutter. The duration betweenthe points "f" and "g" given after the shutter operation has just beenfinished indicates the time when the mirror is being lowered; and theduration between points "h" and "i" indicates the time when the stop isreturned to the full-aperture. Further, the mirror driving motor 12serves also as a mechanical charging means for the focal plane shutter34, and is operated up to a point "j". The completion of the stopdriving (point "l") is transmitted to the microcomputer 10 at the camerabody side 1 through the microcomputer 55, whereby the driving command isemitted to the motor drive circuit 15, thus winding a film through thefilm winding and unwinding motor 14. The winding of the film is finishedat a point "k", with the result that the sequence of the camera isreturned to the original condition, and the photometry/distanceoperation is repeated.

In the illustrated embodiment, the power zoom is not driven during thetime duration between the points 0 and "k" on the basis of theinformation from the camera side 1 to the interchangeable lens side 50(through the conventional serial communication), for example, even ifthe power zoom switch 63 is depressed.

Next, the operation at the interchangeable lens side 50 will beexplained.

FIG. 3 shows a main flow chart of the microcomputer 55 at theinterchangeable lens side 50.

When the power source is turned ON, the microcomputer 55 starts thesequence from a step 101 and goes to a step 102, where various circuitswithin and outside the microcomputer are initialized.

Then, the sequence goes to a step 103, where it is judged whether the AFdriving is being performed or not. If the AF driving is being performed,the sequence goes to a step 104, otherwise, to a step 106.

In the step 104, the value in the counter is read to determine the AFdriving amount, and the read value is compared with a desired AF drivingamount sent from the camera body side 1. If the read value reaches thedesired amount, the sequence goes to a step 105 where the AF driving isstopped, and then goes to the step 106. On the other hand, if the readvalue does not reach the desired AF driving amount, the sequence goes tothe step 106.

In the step 106, the condition of the power zoom switch 63 is judged,and if the switch is turned ON either a side or o side, the sequencegoes to a step 107; whereas, if the switch is turned OFF, the sequencegoes to a step 114.

In the step 114, it is judged whether the zoom driving is beingperformed or not. If the zoom driving is not performed, the sequencereturns to the step 103 and the operations mentioned above is repeated.On the other hand, if the zoom driving is being performed, the sequencegoes to a step 115 where the zoom driving is stopped, and then returnsto the step 103.

If the power zoom switch is turned ON in the step 106, the sequence goesto the step 107, where it is judged whether the zoom driving is beingperformed or not. If the zoom driving is being performed, the sequencegoes to a step 116 where the focal length is detected from the encoder59 for detecting the focal length of the lens, and then goes to a step117.

In the step 117, if the focal length being detected is situated in thezoom end toward which the zoom driving is directed, since a further zoomdriving cannot be effected, the sequence goes to a step 118 where thezoom driving is stopped, and then returns to the step 103. On the otherhand, if the focal length is not situated in the zoom end toward whichthe zoom driving is directed, the zoom driving is further continued, andthen the sequence returns to the step 103.

If the zoom driving is not performed in the step 107, the sequence goesto a step 108 to initiate the zoom driving.

In the step 108, it is judged whether the zoom driving is permitted ornot from a condition of a zoom permission flag in the microcomputer 55.If the zoom driving is permitted, the sequence goes to a step 109;whereas, if not permitted, the sequence returns to the step 103 withoutperforming the zoom driving.

In the step 109, it is judged whether the AF driving is being performedor not. If the AF driving is not performed, the sequence goes to a step112; whereas, if the AF driving is being performed, the sequence goes toa step 110.

In the step 110, a condition of the change-over switch 64 is detectedand it is judged whether the AF priority mode or the zoom priority modeis available. If the AF priority mode is available, the AF driving iscontinued without performing the zoom driving, and then the sequencereturns to the step 103. On the other hand, if the zoom priority mode isavailable, the sequence goes to a step 111 where the AF driving isstopped, and then the sequence goes to the step 112.

In the step 112, it is discriminated whether the power zoom switch 63 isturned ON at the a side or at the c side. If the switch is at the aside, it is judged that the driving should be done in the directiontoward the telephoto side, whereas, if the switch is at the c side, itis judged that the driving should be done in the direction toward thewide-angle side. Thereafter, the sequence goes to a step 113.

In the step 113, the zoom driving is initiated to the driving directiondetermined in the step 112. Then the sequence returns to the step 103,and the sequential operations described above are repeated.

Next, the operation at the initiation of the AF driving will beexplained.

When the microcomputer 55 at the interchangeable lens side 50 receivesthe AF driving command and the AF driving amount from the microcomputer10 at the camera body side 1 through the communication therebetween, themicrocomputer 55 initiates the AF driving by using a known offeringtechnique.

FIG. 4 is a flow chart showing the offering operation regarding the AFdriving command.

In a step 120, when the offering of the AF driving command is entered,the sequence goes to a step 121, where it is judged whether the zoomdriving is being performed or not. If the zoom driving is not performed,the sequence goes to a step 124, whereas, if the zoom driving is beingperformed, the sequence goes to a step 122.

In the step 122, the condition of the power zoom switch 63 isdiscriminated, and, if the zoom priority mode is available, since the AFdriving cannot be performed, the sequence goes to a step 126, where thefact that the zoom priority mode is available and the zoom driving isbeing performed and the AF driving cannot be performed is transmitted tothe microcomputer 10 at the camera body side 1 through thecommunication, and then the sequence goes to a step 127 where theoffering operation is finished. On the other hand, if the AF prioritymode is available in the step 122, the sequence goes to a step 123,where the zoom driving is stopped, and then the sequence goes to thestep 124.

In the step 124, the driving direction information sent from the camerabody side 1 is discriminated, and then the sequence goes to a step 125,where the AF driving is started. Therefore, the sequence goes to thestep 127, thus finishing the offering operation.

Next, the operation regarding the permission and prohibition of the zoomdriving will be explained.

With respect to the prohibition and permission of the zoom driving, inorder to prohibit the zoom driving while the camera body 1 is performingthe operations from the point 0 the point "k" shown in FIG. 2, when thefact that the camera body is performing such operations is detected bythe large current consumption detecting section 10a, the lens movementcontrol section 10b in the microcomputer 10 at the camera body side 1sends the zoom driving prohibition signal to the microcomputer 55 of theinterchangeable lens side 50 at the point 0 in FIG. 2, and sends thezoom driving permission signal to the microcomputer 55 at the point "k"in FIG. 2. The microcomputer 55 at the interchangeable lens side 50treats these signals in a known offering technique.

FIG. 5 is a flow chart showing the operation of the microcomputer 55 ofthe interchangeable lens side 50 when it receives the zoom drivingprohibition signal.

When the microcomputer 55 receives the zoom driving inhibition signal ina step 130, the sequence goes to a step 131, where a zoom prohibitionflag in the microcomputer is set.

Then, the sequence goes to a step 132, where it is judged whether thezoom driving is being performed or not. If the zoom driving is notperformed, the sequence goes to a step 134, where the offering operationis finished. On the other hand, if the zoom driving is being performed,the sequence goes to a step 133, where the zoom driving is stopped, andthen goes to the step 134, thus finishing the offering operation.

FIG. 6 is a flow chart for explaining the operation of the microcomputer55 of the interchangeable lens side 50 when it receives the zoom drivingpermission signal.

When the microcomputer 55 receives the zoom driving permission signal ina step 140, the sequence goes to a step 141, where a zoom prohibitionflag in the microcomputer is reset. Then, the sequence goes to a step142, where the offering operation is finished.

Now, when the zoom prohibition flag is reset, if the power zoom switchhas been turned ON, the zoom driving is initiated as mentioned above.

In the conventional camera system, when the interchangeable lens ismounted on the camera with the power zoom function using the smallerbattery for the portable convenience, the camera sometimes cannot beoperated correctly because it is necessary to provide the large electricpower for performing the power zoom driving. To the contrary, accordingto the illustrated embodiment of the present invention, since the powerzoom driving is prohibited while the large current is consumed in thecamera body side such as in the case of the release operation, shuttercharging operation and/or film feeding operation, it is possible to makethe camera system small-sized without loosing the portable convenience.Further, with this arrangement (i.e., the phototaking is permittedwithout performing the power zoom driving), the camera system consumesthe less energy, thus increasing the number of pictures to be taken.Further, since the power zoom driving is inhibited during the releaseoperation, the obtained pictures are not unpinted ones.

In the illustrated embodiment, while the camera system comprising theinterchangeable lens having the power zoom function and the camera wasexplained, the present invention may be adapted to a camera into which alens having a power zoom function is incorporated. Further, while anexample that the means for discriminating the large current consumptionoperations such as AF driving, stop driving, film feeding and the likeand the means for prohibiting the power zoom driving accordingly arearranged at the camera body was explained, the camera body side mayinclude a battery used as a common power source and the interchangeablelens side may includes such means.

As mentioned above, according to the illustrated embodiment, since thepower zoom driving is prohibited while the driving which consumes thelarge current, such as the AF driving, stop driving and film feeding isbeing performed, thereby using the small battery effectively, theproviding the detecting means for judging whether any driving, otherthan the power zoom driving, which consumes the large current is beingperformed, and the operation control means for prohibiting the powerzoom driving when the fact that any driving which consumes the largecurrent is being performed is detected by the detecting means, it ispossible to the normal photo-taking and to make the camera system moresmall-sized and lighter.

FIG. 7 is a schematic block diagram showing a main construction of acamera system according to a second embodiment of the present invention.Incidentally, the construction of FIG. 7 differs from that of FIG. 1 inthe point that the microcomputer 10 of the camera body 1 does notinclude the large current consumption detecting section 10a and the lensmovement control section 10b and that the change-over switch 64 for theinterchangeable lens 50 is omitted.

Next, the operation of the camera system as constructed above will beexplained.

First of all, the main power source switch 19 of the camera body 1 isturned ON to energize the DC/DC converter 20. As a result, the converter20 supplies a constant operable voltage to the microcomputer 10. Then,when the photometry/distance switch 21 is depressed, the light amountdetected by the photometry light receiving element 6 is transmitted tothe photometry calculating circuit 7, thereby storing the exposureamount in a known manner. Further, since the photometry/distance switch21 serves also as a trigger switch for the autodistance, when thephotometry/distance switch 21 is depressed, the distance sensor 16 isactivated in response to the command from the microcomputer 10, therebyperforming the distance calculation by means of the distance calculatingcircuit 17, determining the feeding amount of the lens, performing theconventional serial communication with the microcomputer 55 at theinterchangeable lens side, and transmitting the rotational direction ofthe lens driving motor 53 to the lens driving circuit 54 to shift theoptical taking lens G1 in a known manner. At the same time, the contentsof the counter 62 is varied through the ratchet 60 in response to themovement of the optical taking lens G1. However, since the microcomputer55 can detect the shifting amount of the lens by reading the number ofpulses counted by the counter, the optical taking lens G1 can be shiftedin accordance with the shifting amount of the lens commanded from thecamera body side as mentioned above, and can be stopped at a focusedposition. Generally, the distance determining operation is performedonce more, and, when the focused condition is ascertained, the focusindication such as visual indication or audible indication is given atthe camera body side 1.

Incidentally, in the second embodiment, the timing of various operationsare the same as those of the previous embodiment shown in FIG. 2, and,thus, the timing of the operations of the camera system of FIG. 7 willbe omitted.

The aim of this second embodiment is that the lens driving motor 53 andthe zoom driving motor 57 are controlled to be energized alternately,when the power zoom switch is being changed at the a side or at the cside, during the AF driving (i.e., while the lens driving motor 53 isbeing rotated). Since a motor has the moment of rotation inherently, ifthe motor is stopped for a short time, the motor continues to rotate,and, accordingly, the above control does not affect the operation of themotor. For example, the lens driving motor 53 and the zoom driving motor57 may be energized alternately every 10 ms (in general, this control iscalled as "duty control"). Therefore, the electric power consumed whenthese motors are rotated is substantially equal to the electric powerconsumed if either motor is continuously rotated.

Next, the operation at the interchangeable lens side 50 will beexplained with reference to a flow chart.

FIG. 8 shows a main flow chart of the microcomputer 55 at theinterchangeable lens side 50.

When the power source is turned ON, the microcomputer 55 starts thesequence from a step 101 and goes to a step 102, where various circuitswithin and outside the microcomputer are initialized.

Then, the sequence goes to a step 103, where it is judged whether the AFdriving is being performed or not. If the AF driving is being performed,the sequence goes to a step 104, otherwise, to a step 106.

In the step 104, the value in the counter is read to determine the AFdriving amount, and the read value is compared with a desired AF drivingamount sent from the camera body side 1. If the read value reaches thedesired amount, the sequence goes to a step 105 where the AF driving isstopped, and then goes to the step 106. On the other hand, if the readvalue does not reach the desired AF driving amount, the sequence goes tothe step 106.

In the step 106, the condition of the power zoom switch 63 is judged,and if the switch is turned ON either a side or c side, the sequencegoes to a step 107; whereas, if the switch is turned OFF, the sequencegoes to a step 113.

In the step 113, it is judged whether the zoom driving is beingperformed or not. If the zoom driving is not performed, the sequencereturns to the step 103 and the operations mentioned above is repeated.On the other hand, if the zoom driving is being performed, since thepower zoom switch is turned OFF, the sequence goes to a step 114 wherethe zoom driving is stopped, and then returns to the step 103.

If the power zoom switch is turned ON in the step 106, the sequence goesto the step 107, where it is judged whether the zoom driving is beingperformed or not. If the zoom driving is being performed, the sequencegoes to a step 115 where the focal length is detected from the encoder59 for detecting the focal length of the lens, and then goes to a step116.

In the step 116, if the focal length being detected is situated in thezoom end toward which the zoom driving is directed, since a further zoomdriving cannot be effected, the sequence goes to a step 117 where thezoom driving is stopped, and then returns to the step 103. On the otherhand, if the focal length is not situated in the zoom end toward whichthe zoom driving is directed, the zoom driving is further continued, andthen the sequence returns to the step 103.

If the zoom driving is not performed in the step 107, the sequence goesto a step 108 to initiate the zoom driving.

In the step 108, it is judged whether the zoom driving is permitted ornot from a condition of a zoom permission flag in the microcomputer 55.If the zoom driving is permitted, the sequence goes to a step 109;whereas, if not permitted, the sequence returns to the step 103 withoutperforming the zoom driving.

In the step 109, it is discriminated whether the power zoom switch 63 isturned ON at the a side or at the c side. If the switch is at the aside, it is judged that the driving should be done in the directiontoward the telephoto side, whereas, if the switch is at the c side, itis judged that the driving should be done in the direction toward thewide-angle side. Thereafter, the sequence goes to a step 110.

In the step 110, it is judged whether the AF driving is being performedor not. If the AF driving is not performed, the sequence goes to a step112; whereas, if the AF driving is being performed, the sequence goes toa step 111.

In the step 111, in order to perform the AF driving and the zoom drivingsimultaneously, the AF driving motor 53 and the zoom driving motor 57are energized alternately, thereby decreasing the speed of the AFdriving so that the zoom driving is started to the direction determinedin the step 109, and then the sequence returns to the step 103, fromwhere the operations mentioned above are repeated.

In the step 112, since only the zoom is effected, the zoom driving motor57 is always energized (it means that the duty control is not effected),whereby the zoom driving is started to the direction determined in thestep 109 at a speed faster than a speed at which the AF driving and thezoom driving are simultaneously performed. Thereafter, the sequencereturns to the step 103.

Next, the operation at the initiation of the AF driving will beexplained with reference to a flow chart shown in FIG. 9.

When the microcomputer 55 at the interchangeable lens side 50 receivesthe AF driving command and the AF driving amount from the microcomputer10 at the camera body side 1 through the communication therebetween, themicrocomputer 55 initiates the AF driving by using a known offeringtechnique.

In a step 120, when the offering of the AF driving command is entered,the sequence goes to a step 121 where the driving direction sent fromthe camera body side 1 is judged, and then goes to a step 122. In thestep 122, it is judged whether the zoom driving is being performed ornot. If the zoom driving is not performed, the sequence goes to a step124, whereas, if the zoom driving is being performed, the sequence goesto a step 123.

In the step 123, in order to perform the AF driving and the zoom drivingsimultaneously, the AF driving motor 53 and the zoom driving motor 57are energized alternately, thereby decreasing the speed of the AFdriving so that the AF driving is started at a low speed to thedirection determined in the step 121, and then the sequence goes to thestep 125, where the offering operation is finished.

On the other hand, in the step 124, since only the zoom is effected, thezoom driving motor 57 is always energized, whereby the AF driving isstarted to the direction determined in the step 121 at a speed fasterthan a speed at which the AF driving and the zoom driving aresimultaneously performed. Thereafter, the sequence goes to the step 125,thus finishing the offering operation.

Next, the operation regarding the permission and prohibition of the zoomdriving will be explained.

With respect to the prohibition and permission of the zoom driving, inorder to prohibit the zoom driving while the camera body 1 is performingthe operations from the point 0 to the point "k" shown in FIG. 2, themicrocomputer 10 at the camera body side 1 sends the zoom drivingprohibition signal to the microcomputer 55 of the interchangeable lensside 50 at the point 0 in FIG. 2, and sends the zoom driving permissionsignal to the microcomputer 55 at the point "k" in FIG. 2. Themicrocomputer 55 at the interchangeable lens side 50 treats thesesignals in a known offering technique.

FIG. 10 is a flow chart showing the operation of the microcomputer 55 ofthe interchangeable lens side 50 when it receives the zoom drivingprohibition signal.

When the microcomputer 55 receives the zoom driving inhibition signal ina step 130, the sequence goes to a step 131, where a zoom prohibitionflag in the microcomputer is set.

Then, the sequence goes to a step 132, where it is judged whether thezoom driving is being performed or not. If the zoom driving is notperformed, the sequence goes to a step 134, where the offering operationis finished. On the other hand, if the zoom driving is being performed,the sequence goes to a step 133, where the zoom driving is stopped, andthen goes to the step 134, thus finishing the offering operation.

FIG. 11 is a flow chart for explaining the operation of themicrocomputer 55 of the interchangeable lens side 50 when it receivesthe zoom driving permission signal.

When the microcomputer 55 receives the zoom driving permission signal ina step 140, the sequence goes to a step 141, where a zoom prohibitionflag in the microcomputer is reset. Then, the sequence goes to a step142, where the offering operation is finished.

Now, when the zoom prohibition flag is reset, if the power zoom switch63 has been turned ON, the zoom driving is initiated as mentioned above.

FIG. 12 is a schematic block diagram showing a main construction of acamera system according to a third embodiment of the present invention.Incidentally, the same or similar elements as those shown in FIG. 1 willbe designated by the same reference numerals used in FIG. 1.

In FIG. 12, the reference numerals 64a, 65b denote constant currentcircuits, the constant current being set to have a value of 1/2 of thecurrents consumed by the lens driving motor 53 and the zoom drivingmotor 57. The reference numerals 66, 67 denote switches which can beopened in response to the command from the microcomputer 55.

Either the AF driving or the power zoom driving is to be performed, theswitches 66, 67 is maintained in the ON conditions so that the normaldriving is performed. On the other hand, when the AF driving and thepower zoom driving are simultaneously performed, the switches 66, 67 arechanged to the OFF conditions so that the 1/2 of the current is appliedto the respective motor 53 and 57.

In the above mentioned second and third embodiments, even if the AFdriving and the zoom driving are performed simultaneously, the consumedcurrent corresponds to the current consumed by a single motor.Accordingly, the battery 18 may be small-sized, and, thus, it ispossible to make the camera system more small-sized and lighter, and tomeet the requirements regarding substantially all of the shutterchances. Further, since the consumed current is small even when the AFdriving and the zoom driving are simultaneously performed, it ispossible to solve the problem that the correct or normal photo-takingcannot be effected.

FIG. 13 is a schematic block diagram showing a main construction of acamera system according to a fourth embodiment of the present invention.Incidentally, the same or similar elements as those shown in FIG. 1 willbe designated by the same reference numerals used in FIG. 1.

In FIG. 12, the reference numeral 68 denotes a voltage detecting circuitfor monitoring the voltage (of the battery 18) on a power source line,which is applied from the camera body side 1 to the interchangeable lensside 50. The voltage detecting circuit may comprise a conventional A/Dconverter and the like.

As is known, when the battery 18 is new, it has the largest capacity(electric power) and provides the high voltage at its output terminal.In such a case, it is possible to energize a number of motorssimultaneously. However, if the battery becomes old, its terminalvoltage is decreased and it will be impossible to energize a number ofmotors simultaneously. Accordingly, in the illustrated embodiment, whenthe fact that the voltage on the power source line decreases below apredetermined value by means of the voltage detecting circuit 68, thesimultaneous energizations of the plural motors are prevented.

Next, the operation at the interchangeable lens side 50 will beexplained with reference to a flow chart.

FIG. 14 shows a main flow chart of the microcomputer 55 at theinterchangeable lens side 50. From a step 101 to a step 108, and from astep 113 to a step 117, the operation is the same as that of FIG. 8,and, thus, the explanation of thereof will be omitted.

In a step 151, it is judged whether the AF driving is being performed ornot. If the AF driving is not performed, the sequence goes to a step153, whereas, if the AF driving is being performed, the sequence goes toa step 152.

In the step 152, the power source voltage is detected by the voltagedetecting circuit 68, and, if the power source voltage is more than agiven voltage, since the AF driving and the zoom driving can beperformed simultaneously, the sequence goes to the step 153. On theother hand, if the power source voltage is lower than the given voltage,since the AF driving and the zoom driving cannot be performedsimultaneously, the AF driving is continued, and then the sequencereturns to the step 103 without performing the zoom driving.

In the step 153, it is discriminated whether the power zoom switch 63 isturned ON at the a side or at the c side. If the switch is at the aside, it is judged that the driving should be done in the directiontoward the telephoto side, whereas, if the switch is at the c side, itis judged that the driving should be done in the direction toward thewide-angle side. Thereafter, the sequence goes to a step 154.

In the step 154, the zoom driving is performed toward the directiondiscriminated in the step 153, and then the sequence returns to the step103, from where the operations mentioned above are repeated.

Next, the operation at the initiation of the AF driving will beexplained.

FIG. 15 is a flow chart showing the offering operation regarding the AFdriving command.

In a step 160, when the offering of the AF driving command is entered,the sequence goes to a step 161, where it is judged whether the zoomdriving is being performed or not. If the zoom driving is not performed,the sequence goes to a step 163, whereas, if the zoom driving is beingperformed, the sequence goes to a step 162.

In the step 162, if the power source voltage is more than the givenvoltage, since the AF driving and the zoom driving can be performedsimultaneously, the sequence goes to the step 163. On the other hand, ifthe power source voltage is below the given voltage, since the AVdriving and the zoom driving cannot be performed simultaneously, thezoom driving is continued. Thereafter, the sequence goes to a step 165without executing the AF driving, where the signal representing the factthat the AF driving cannot be performed is sent to the microcomputer 10of the camera body 1, and then goes to a step 166, where the offeringoperation is finished.

In the step 163, the driving direction sent from the camera body 1 isdiscriminated. Then, the sequence goes to a step 164 where the AFdriving is started, and then goes to the step 166, thus finishing theoffering operation.

In the above second and third embodiments of the invention, even if theAF driving and the zoom driving were performed simultaneously, theconsumed current corresponded to the current consumed by a single motor.Accordingly, the battery might be small-sized, and, thus, it waspossible to make the camera system more small-sized and to increase thenumber of pictures to be taken due to the lesser energy consumption.

According to the fourth embodiment of the present invention, since whenthe power source voltage is high (in other words, when the battery isnew) the simultaneous execution of the AF driving and the zoom drivingis permitted and when the power source voltage is decreased (i.e., whenthe battery becomes old) the simultaneous execution of the AF drivingand the zoom driving is prohibited, the power source can be effectivelyutilized and a small battery 18 can be used, thus making the camerasystem itself small-sized. Further, since the camera system is soconstructed that at least the photo-taking operation can be effectedeven if the power source voltage is decreased, the number of pictures tobe taken will be increased.

Further, in the above-mentioned second and third embodiments, while thecamera system was constructed that the consumed current corresponded tothe current consumed by a single motor when the AF driving and the zoomdriving were simultaneously performed, by using the duty control or theconstant current control (which may be the constant voltage control), itmay include a voltage detecting circuit as shown in the fourthembodiment and may be constructed that the above controls are carriedout only when the fact that the power source voltage is decreased belowthe predetermined value is detected by the voltage detecting circuit. Inthis way, the camera can meet the requirements regarding substantiallyall of the shutter chances.

Further, in the fourth embodiment, while an example that the compactnessof the camera system can be attained by prohibiting the simultaneousexecution of the AF driving and the zoom driving when the power sourcevoltage is below the predetermined value was explained, the camerasystem may include any circuits for performing the duty control and/orthe constant current control shown in the second and third embodimentsand may be constructed that such controls are carried out when the powersource voltage is maintained between a first predetermined value and asecond predetermined value smaller than the first one. In this way, thecamera system can meet the requirements regarding substantially all ofthe shutter chances more effectively in comparison with the camerasystem of the fourth embodiment.

Further, in the above-mentioned second and third embodiments, whilemeans for performing the duty control and/or the constant currentcontrol were arranged at the interchangeable lens side 50, these meansmay be arranged at the camera body side 1. Similarly, in the fourthembodiment, while the voltage detecting circuit was arranged at theinterchangeable lens side 50, it may be arranged at the camera body side1.

As mentioned above, according to the second, third and fourthembodiments of the present invention, by providing the drive controlmeans for carrying out the AF driving and the zoom driving with theconsumption current smaller than that consumed by simultaneously andindependently performing the AF and zoom drivings, the simultaneousexecution of the power zoom driving and the AF driving can be effectedwith the current which is equal to the current consumed by performingeither one of these drivings; and by providing the power source voltagedetecting means for discriminating whether the voltage of the battery ismore or below than the predetermined value, and the operation controlmeans for prohibiting the simultaneous execution of the power zoom andAF drivings when the fact that the power source voltage is below thepredetermined value is detected by the voltage detecting means, eitherof the AF driving or the power zoom driving can be prevented when thepower source voltage is below the predetermined value so that the smallbattery can be effectively used. Accordingly, it is possible to solvethe problem that the normal photo-taking cannot be carried out, to makethe camera system more small-sized and lighter, and to make the camerasystem stronger with respect to the shutter chances.

Next, a fifth embodiment of the present invention will be explained.

Since the construction of the camera system according to the fifthembodiment is substantially the same as that shown in FIG. 1 except thatthe microcomputer 10 does not include the large current consumptiondetecting section 10a and the lens movement control section 10b, thedetailed explanation thereof will be omitted.

Hereinafter, the fifth embodiment of the invention will be fullyexplained with reference to a main flow chart of the microcomputer 55 atthe interchangeable lens side 50 as shown in FIG. 16.

When the power source is turned ON, the microcomputer 55 starts thesequence from a step 101 and goes to a step 102, where various circuitswithin and outside the microcomputer are initialized.

Then, the sequence goes to a step 103, where it is judged whether the AFdriving is being performed or not. If the AF driving is being performed,the sequence goes to a step 104, otherwise, to a step 106.

In the step 104, the value in the counter is read to determine the AFdriving amount, and the read value is compared with a desired AF drivingamount sent from the camera body side 1. If the read value reaches thedesired amount, the sequence goes to a step 105 where the AF driving isstopped, and then goes to the step 106. On the other hand, if the readvalue does not reach the desired AF driving amount, the sequence goes tothe step 106.

In the step 106, the condition of the power zoom switch 63 is judged,and if the switch is turned ON either a side or c side, the sequencegoes to a step 107; whereas, if the switch is turned OFF, the sequencegoes to a step 113.

In the step 113, it is judged whether the zoom driving is beingperformed or not. If the zoom driving is not performed, the sequencereturns to the step 103 and the operations mentioned above is repeated.On the other hand, if the zoom driving is being performed, the sequencegoes to a step 114 where the zoom driving is stopped, and then returnsto the step 103.

If the power zoom switch is turned ON in the step 106, the sequence goesto the step 107, where it is judged whether the zoom driving is beingperformed or not. If the zoom driving is being performed, the sequencegoes to a step 115 where the focal length is detected from the encoder59 for detecting the focal length of the lens, and then goes to a step116.

In the step 116, if the focal length being detected is situated in thezoom end toward which the zoom driving is directed, since a further zoomdriving cannot be effected, the sequence goes to a step 117 where thezoom driving is stopped, and then returns to the step 103. On the otherhand, if the focal length is not situated in the zoom end toward whichthe zoom driving is directed, the zoom driving is further continued, andthen the sequence returns to the step 103.

If the zoom driving is not performed in the step 107, the sequence goesto a step 108 to initiate the zoom driving.

In the step 108, it is judged whether the AF driving is being performedor not. If the AF driving is not performed, the sequence goes to a step111, whereas, if the AF driving is being performed, the sequence goes toa step 109.

In the step 109, a condition of the change-over switch 64 is detectedand it is judged whether the AF priority mode or the zoom priority modeis available. If the AF priority mode is available, the AF driving iscontinued without performing the zoom driving, and then the sequencereturns to the step 103. On the other hand, if the zoom priority mode isavailable, the sequence goes to a step 110 where the AF driving isstopped, and then the sequence goes to the step 111.

In the step 111, it is discriminated whether the power zoom switch 63 isturned ON at the a side or at the c side. If the switch is at the aside, it is judged that the driving should be done in the directiontoward the telephoto side, whereas, if the switch is at the c side, itis judged that the driving should be done in the direction toward thewide-angle side. Thereafter, the sequence goes to a step 112.

In the step 112, the zoom driving is started to the driving directiondetermined in the step 111. Then the sequence returns to the step 103,and the sequential operations described above are repeated.

Next, the operation at the initiation of the AF driving will beexplained.

When the microcomputer 55 at the interchangeable lens side 50 receivesthe AF driving command and the AF driving amount from the microcomputer10 at the camera body side 1 through the communication therebetween, themicrocomputer 55 initiates the AF driving by using a known offeringtechnique.

Since a flow chart showing the offering operation regarding the AFdriving command is the same as that shown in FIG. 4, the explanationthereof will be omitted.

According to the fifth embodiment of the present invention, since, inthe zoom priority mode, if the AF driving is being performed when thezoom driving should be performed, the AF driving is stopped and the zoomdriving is performed (steps 108→109→110 111→. . . in FIG. 16, and steps121→122→126→. . . in FIG. 4), and, in the AF priority mode, if the zoomdriving is being performed when the AF driving should be performed, thezoom driving is stopped and the AF driving is performed (steps121→122→123→124→. . . in FIG. 4, and steps 108→109→103→. . . in FIG.16), i.e., since the simultaneous execution of the power zoom drivingand the AF driving is prohibited, the power source can be madesmall-sized and the normal or correct operation can be ensured. Further,since the power source can be utilized effectively, the number of filmswhich can be properly photo-taken can be increased.

Further, for example, if the zoom driving is carried out while the AFdriving is being performed, an image on the distance sensor 16 is variedor changed, which frequently leads in the incorrect distance measuring.However, according to the fifth embodiment of the invention, since thezoom driving is prohibited when the AF priority mode is selected, theimage on the distance sensor 16 is not varied, and, thus, it is possibleto measure the distance correctly. That is to say, since not only thesimultaneous execution of the AF driving and the zoom driving isprohibited but also any one of these drivings can be preferentiallyperformed, it is possible to take a photograph more properly.

As mentioned above, according to the fifth embodiment of the presentinvention, by providing the operation control means for prohibiting thesimultaneous execution of the power zoom driving and the AF driving, thepower zoom driving is prohibited while the AF driving is being performedand the AF driving is prohibited while the power zoom driving is beingperformed; and by providing the selection means for selecting the powerzoom priority mode and the AF priority mode, and the priorityinstructing means for preferentially performing the power zoom drivingto the AF driving when the power zoom priority mode is selected and forpreferentially performing the AF driving to the power zoom driving whenthe AF priority mode is selected, the respective driving can be at anydesired timing. Accordingly, the small battery can be utilizedeffectively and it is possible to always carry out the properphoto-taking.

Next, a sixth embodiment of the present invention will be explained.

Prior to the explanation of the construction of the sixth embodiment ofthe invention, a prior art relating to this embodiment will beexplained.

In a conventional photo-taking apparatus of the power zoom type, thefollowing two methods for stopping the zoom driving at the telephoto endand at the wideangle end were adopted.

In the first method, mechanical contact switches such as limit switchesare arranged at positions corresponding to the telephoto end and thewide-angle end, and a zoom driving motor is stopped when the fact that amoving member such as a magnification changing lens holder is engaged bythe mechanical switch during the zoom driving is detected.

In the second method, the rotating amount of a zoom driving motor duringthe zoom driving is detected by a conventional encoder as electricpulses, and the zoom driving motor is stopped when the sum of the numberof pulses corresponds to a distance up to the telephoto end andwide-angle end.

In case of the above first method, if the switches are positioned withvery high accuracy, the magnification changing lens holder can becorrectly stopped at the position corresponding to the telephoto end orthe wide-angle end. However, in the actual manufacturing process, sinceit is impossible to position the switches at the desired positions withvery high accuracy, the first method leads to the following drawbacks.

That is to say, if the switches are arranged ahead of the telephoto endand/or the wide-angle end, since the switch is activated before themagnification changing lens holder reaches the telephoto end orwide-angle end to stop the zoom driving motor, the magnificationchanging lens holder will be stopped before it reaches the telephoto endor wide-angle end.

On the other hand, if the switches are arranged beyond the telephoto endand/or the wide-angle end, since the switch is not activated when themagnification changing lens holder reaches the telephoto end orwide-angle end, the energization of the zoom driving motor is continued,with the result that the excessive load is applied to the powertransmission mechanism and/or the useless electric power is consumed.

On the other hand, in case of the above second method, since it isnecessary to provide a specific motor control circuit for correctlystopping the zoom driving motor when a means for detecting therotational amount of the zoom driving motor and/or the magnificationchanging lens reaches the telephoto end or the wide-angle end, themanufacturing cost is increased.

An object of the sixth embodiment of the present invention is to providean improved zoom driving controlling method which can eliminate theincorrect stop position and avoid the increase in the manufacturingcost.

Hereinafter, the sixth embodiment of the present invention will be fullyexplained.

Since the construction of the camera system according to the sixthembodiment is substantially the same as that shown in FIG. 1 except thatthe microcomputer 10 does not include the large current consumptiondetecting section 10a and the lens movement control section 10b, thedetailed explanation thereof will be omitted.

FIG. 17 shows a main flow chart of the microcomputer 55 at theinterchangeable lens side.

When the power source is turned ON, the microcomputer 55 starts thesequence from a step 101 and goes to a step 102, where various circuitswithin and outside the microcomputer are initialized.

Then, the sequence goes to a step 103, where it is judged whether the AFdriving is being performed or not. If the AF driving is being performed,the sequence goes to a step 104, otherwise, to a step 106.

In the step 104, the value in the counter 62 us read to determine the AFdriving amount, and the read value is compared with a desired AF drivingamount sent from the camera body side 1. If the read value reaches thedesired amount, the sequence goes to a step 105 where the AF driving isstopped, and then goes to the step 106. On the other hand, if the readvalue does not reach the desired AF driving amount, the AF driving iscontinued, and then the sequence goes to the step 106.

In the step 106, the condition of the power zoom switch 63 is judged,and if the switch is turned ON either a side or c side, the sequencegoes to a step 107; whereas, if the switch is turned OFF, the sequencegoes to a step 114. In the step 114, it is judged whether the zoomdriving is being performed or not. If the zoom driving is not performed,the sequence returns to the step 103 and the operations mentioned aboveis repeated. On the other hand, if the zoom driving is being performed,since the power zoom switch is turned OFF, the sequence goes to a step115 where the zoom driving is stopped, and then returns to the step 103.

Then, if the power zoom switch is turned ON in the step 106, thesequence goes to the step 107, where it is judged whether the zoomdriving is bent performed or not. If the zoom driving is beingperformed, the sequence goes to a step 116 where the focal length isdetected from the encoder 59 for detecting the focal length of the lens,and then goes to a step 117.

In the step 117, the zoom is driven toward the wide-angle side, when thefocal length near the wideangle end is detected, since the zoom willsoon reach the wide-angle end, the sequence goes to a step 118 where azoom end timer in the microcomputer is turned ON, and then goes to astep 119. On the other hand, in the step 118, if the focal length is notsituated in wide-angle end, the sequence returns to the step 103.

Here, while an example that the zoom is driven toward the wide-angleside was explained, similarly, if the zoom is driven toward thetelephoto side, when the fact that the focal length is situated at thetelephoto end is detected, the zoom end timer is turned ON, and thesequence goes to the step 119.

In the step 119, it is judged whether the zoom timer turned ON in thestep 118 is driven for a given period or not. If not, the sequencereturns to the step 119 again. On the other hand, if the timer is drivenfor the given period, the sequence goes to a step 120, where the zoomdriving is stopped.

On the other hand, if the zoom driving is not performed in the step 107,the sequence goes to a step 108 to initiate the zoom driving, where itis judged whether the zoom driving is permitted or prohibited.

If the zoom driving is prohibited, the sequence returns to the step 103,whereas, if the zoom driving is permitted, the sequence goes to a step109. Incidentally, when the camera body requires the large electricpower, the zoom prohibition command is sent from the microcomputer 10 ofthe camera body to the microcomputer 55 of the interchangeable lensthrough the serial communication therebetween.

In the step 109, it is judged whether the AF driving is being performedor not. If the AF driving is not performed, the sequence goes to a step111, whereas, if the AF driving is being performed, the sequence goes toa step 110. In the step 110, a condition of the switch 64 is detectedand it is judged whether the AF priority mode or the zoom priority modeis available. If the AF priority mode is available, the AF driving iscontinued without performing the zoom driving, and then the sequencereturns to the step 103. On the other hand, if the zoom priority mode isavailable, the sequence goes to the step 111 where the AF driving isstopped, and then goes to a step 112.

In the step 112, it is discriminated whether the zoom switch 63 isturned ON either at the a side or at the c side. If the switch is at thea side, it is judged that the driving should be done in the directiontoward the telephoto side, whereas, if the switch is at the c side, itis judged that the driving should be done in the direction toward thewide-angle side, and then the sequence goes to a step 113. In the step113, the zoom driving is started in the driving direction discriminatedin the step 112, and then the sequence returns to the step 103, fromwhere the above-mentioned operations are repeated.

As mentioned above, in the zoom driving control method shown in thesixth embodiment of the present invention, since when the focal lengthdetecting means detects the focal length situated nearest the wide-angleend or the telephoto end, the zoom end timer arranged in themicrocomputer is turned ON, whereby the zoom driving is stopped for thegiven period, the zoom driving can be effectively stopped without usingany additional elements for detecting the zoom end or without adjustingthe zoom end.

What is claimed is:
 1. A camera system comprising:(a) a zoom drivingmeans driven by a battery as a power source, for varying a focal lengthof a taking lens; (b) at least one other driving means driven by saidbattery as a power source; (c) a detecting means for detecting whetherany of said other driving means is being executed or is to be executed;and (d) a control means for prohibiting the execution of said zoomdriving means when said detecting means detects the fact that any ofsaid other driving means is being executed or is to be executed.
 2. Acamera system according to claim 1, wherein said control means prohibitssimultaneous execution of an auto-focus driving means and said zoomdriving means.
 3. A camera system according to claim 1, wherein saidcontrol means prohibits simultaneous execution of an aperture-stopdriving means and said zoom driving means.
 4. A camera system accordingto claim 1, wherein said control means prohibits simultaneous executionof a mirror driving means and said zoom driving means.
 5. A camerasystem according to claim 1, wherein said control means prohibitssimultaneous execution of a shutter charging means and said zoom drivingmeans.
 6. A camera system according to claim 1, wherein said controlmeans prohibits simultaneous execution of a film feeding means and saidzoom driving means.
 7. A camera body on which an interchangeable lenshaving a zoom driving means driven by a motor and adapted to vary afocal length is mountable, comprising:(a) a power source means acting asa power source for said zoom driving means; (b) a supply means forsupplying power from said power source means to said interchangeablelens; (c) a first driving means driven by said power from said powersource means; (d) a detecting means for detecting whether said firstdriving means is being executed or said first driving means is to beexecuted; and (e) a control means for outputting a signal representativeof the prohibition of execution of said zoom driving means to saidinterchangeable lens, when said detecting means detects the fact thatsaid first driving means is being executed or that said first drivingmeans is to be executed.
 8. A camera body according to claim 7, whereinsaid interchangeable lens can be electrically connected to said camerabody through a plurality of contacts.
 9. A camera body according toclaim 7, wherein said first driving means comprises a mirror drivingmeans.
 10. A camera body according to claim 7, wherein said firstdriving means comprises a shutter charging means.
 11. A camera bodyaccording to claim 7, wherein said first driving means comprises a filmfeeding means.
 12. An interchangeable lens mountable on a camera bodyhaving a power source means, a supply means for supplying power fromsaid power source means to said interchangeable lens, a first drivingmeans driven by said power from said power source means, and a controlmeans for outputting a signal representative of the prohibition to saidinterchangeable lens when said first driving means being executed or isto be executed so that said first driving means and a second drivingmeans provided in said interchangeable lens are not executedsimultaneously, comprising:(a) a zoom driving means driven by said powerfrom said power source means, for varying a focal length of saidinterchangeable lens; and (b) a second control means for controlling theexecution of said zoom driving means, said second control meansprohibiting the execution of said zoom driving means when it receivessaid signal representative of prohibition.
 13. An interchangeable lensaccording to claim 12, wherein said interchangeable lens can beelectrically connected to said camera body through a plurality ofcontacts.
 14. An interchangeable lens according to claim 12, whereinsaid first driving means comprises a mirror driving means.
 15. Aninterchangeable lens according to claim 12, wherein said first drivingmeans comprises a shutter charging means.
 16. An interchangeable lensaccording to claim 12 wherein said first driving means comprises a filmfeeding means.
 17. A camera body on which an interchangeable lens havinga zoom driving means driven by a motor and adapted to vary a focallength and at least one other driving means is mountable, comprising:(a)a power source means acting as a power source for said zoom drivingmeans and said other driving means; (b) a supply means for supplyingpower from said power source means to said interchangeable lens; (c) adetecting lens for detecting whether any of said other driving means isbeing executed or is to be executed; and (d) a control means foroutputting a signal representative of the prohibition of execution ofsaid zoom driving means to said interchangeable lens, when saiddetecting means detects the fact that any of said other driving means isbeing executed or is to be executed.
 18. A camera body according toclaim 17, wherein said interchangeable lens can be electricallyconnected to said camera body through a plurality of contacts.
 19. Acamera body according to claim 17, wherein said other driving meanscomprises an auto-focus driving means.
 20. A camera body according toclaim 17, wherein said other driving means comprises a stop drivingmeans.
 21. An interchangeable lens mountable on a camera body having apower source means, a supply means for supplying power from said powersource means to said interchangeable lens, and a control means forsupplying a signal representative of the prohibition to saidinterchangeable lens so that a first driving means and a second drivingmeans each driven by said power from said power source means andarranged in said interchangeable lens are not executed simultaneouslywherein;(a) said first driving means can vary a focal length of saidinterchangeable lens; and, comprising: (b) a second control means forcontrolling the execution of said first driving means, said secondcontrol means inhibiting the execution of said first driving means whenit receives said signal representative of prohibition.
 22. Aninterchangeable lens according to claim 21, wherein said second drivingcomprises an auto-focus driving means.
 23. An interchangeable lensaccording to claim 21, wherein said second driving comprises a stopdriving means.
 24. An interchangeable lens according to claim 21,wherein said interchangeable lens can be electrically connected to saidcamera body through a plurality of contacts.
 25. A camera systemcomprising:(a) a zoom driving means driven by a battery as a powersource, for varying a focal length of a taking lens; (b) at least oneother driving means driven by said battery as a power source; and (c) acontrol means for executing said zoom driving means and said at leastone other driving means, respectively, with consumption current smallerthan that consumed by executing said zoom driving means of any of saidother driving means solely, when said zoom driving means and any of saidother driving means are simultaneously executed.
 26. A camera systemaccording to claim 25, wherein said control means executes said zoomdriving means and said other driving means at a low speed when thesedriving means are simultaneously executed.
 27. A camera system accordingto claim 25, wherein said other driving means comprises an auto-focusdriving means.
 28. A camera system according to claim 27, wherein saidcontrol means executes said zoom driving means and said auto-focusdriving means at a low speed when these driving means are simultaneouslyexecuted.
 29. A camera body on which an interchangeable lens having azoom driving means driven by a motor and adapted to vary a focal lengthand at least one other driving means is mountable, comprising:(a) apower source means acting as a power source for said zoom driving means;(b) a supply means for supplying power from said power source means tosaid interchangeable lens; and (c) a control means for executing saidzoom driving means and said other driving means, respectively, withconsumption current smaller than that consumed by executing said zoomdriving means or said other driving means solely, when said zoom drivingmeans and any of said other driving means is simultaneously executed.30. A camera system according to claim 29, wherein said control meansexecutes said zoom driving means and said other driving weans at a lowspeed when these driving means are simultaneously executed.
 31. A camerasystem according to claim 29, wherein said other driving means comprisesan auto-focus driving means.
 32. A camera system according to claim 31,wherein said control means executes said zoom driving means and saidauto-focus driving means at a low speed when these driving means aresimultaneously executed.
 33. An interchangeable lens mountable on acamera body having a power source means, a supply means for supplyingpower from said power source means to said interchangeable lens, and acontrol means for supplying a signal for executing two driving meansarranged in said interchangeable lens respectively with consumptioncurrent smaller than that consumed by executing said driving meanssolely when these two driving means are simultaneously executed, to saidinterchangeable lens, comprising:(a) a zoom driving means driven by saidpower from said power source means, for varying a focal length of saidinterchangeable lens; (b) at least one other driving means driven bysaid power from said power means; and (c) a second control means forexecuting said zoom driving means and said at least one other drivingmeans, respectively, with consumption current smaller than that consumedby executing said zoom driving means or any of said other driving meanssolely, when it receives said signal.
 34. A camera system according toclaim 33, wherein said second control means executes said zoom drivingmeans and said other driving means at a low speed when these drivingmeans are simultaneously executed.
 35. A camera system according toclaim 33, wherein said other driving means comprises an auto-focusdriving means.
 36. A camera system according to claim 35, wherein saidsecond control means executes said zoom driving means and saidauto-focus driving means at a low speed when these driving means aresimultaneously executed.
 37. A camera system comprising:(a) a zoomdriving means driven by a battery as a power source, for varying a focallength of a taking lens; (b) at least one other driving means driven bysaid battery as a power source; (c) a detecting means for detecting avoltage level of said battery; and (d) a control means for prohibitingthe simultaneous execution of said zoom driving means and any of saidother driving means when said detecting means detects the fact that saidvoltage level is below a predetermined value.
 38. A camera systemaccording to claim 37, wherein said other driving means comprises anauto-focus driving means.
 39. A camera body on which an interchangeablelens having a zoom driving means driven by a motor and adapted to varyfocal length and at least one other driving means is mountable,comprising:(a) a power source means acting as a power source for saidzoom driving means; (b) a supply means for supplying power from saidpower source means to said interchangeable lens; (c) a detecting meansfor detecting a voltage level of said battery; and (d) a control meansfor prohibiting the simultaneous execution of said zoom driving meansand said other driving means when said detecting means detects the factthat said voltage level is below a predetermined value.
 40. Aninterchangeable lens mountable on a camera body having a power sourcemeans, a supply means for supplying power from said power source meansto said interchangeable lens, a detecting means for detecting a voltagelevel of said power source means, and a control means for supplying asignal for prohibiting the simultaneous execution of two driving meanswhen said detecting means detects the fact that said voltage level isbelow a predetermined value, to said interchangeable lens,comprising:(a) a zoom driving means driven by said power from said powersource means, for varying a focal length of said interchangeable lens;and (b) at least one other driving means driven by said power from saidpower source means; and (c) a second control means for prohibiting thesimultaneous execution of said zoom driving means and any of said otherdriving means when it receives said signal.
 41. An interchangeable lensaccording to claim 40, wherein other driving means comprises anauto-focus driving means.